The influence of water temperature on protein composition in the reconstitution of milk powder was evaluated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). 11 ion ...The influence of water temperature on protein composition in the reconstitution of milk powder was evaluated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). 11 ion peaks in the matrix-assisted laser desorption/ionization (MALDI) spectra were examined to study the alteration of relative quantities of milk proteins when water at different temperature was employed in the reconstitution of milk powder. A discrepancy factor Dij was implemented to represent the degree of milk proteins' denaturation. Data obtained indicated that Dij value increased with rising water temperature, and thermal damage to milk proteins became evidently when the water temperature exceeded 60℃. The results confirmed that nutrient loss occurred when milk proteins denatured in water at high temperatures.展开更多
文摘The influence of water temperature on protein composition in the reconstitution of milk powder was evaluated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). 11 ion peaks in the matrix-assisted laser desorption/ionization (MALDI) spectra were examined to study the alteration of relative quantities of milk proteins when water at different temperature was employed in the reconstitution of milk powder. A discrepancy factor Dij was implemented to represent the degree of milk proteins' denaturation. Data obtained indicated that Dij value increased with rising water temperature, and thermal damage to milk proteins became evidently when the water temperature exceeded 60℃. The results confirmed that nutrient loss occurred when milk proteins denatured in water at high temperatures.